Taiwan Semiconductor Manufacturing Comp. Ltd.

Jui-Hung Ho

Chin-Szu Lee

Szu-Hua Wu

Jung-Tang Wu

Meng-Yu Wu

Chi-Hung Liao

Chia-Hung Tsai

Yu-Jen Chien

A magnetic shield reduces external noise in a chamber including a target and at least one electromagnet for copper physical vapor deposition (PVD). The shield may have a thickness in a range from approximately 0.1 mm to approximately 10 mm to provide sufficient protection from radio frequency and other electromagnetic signals. As a result, copper atoms in the chamber undergo less re-direction from external noise. Additionally, even when hardware failure occurs during PVD (e.g., an electromagnet malfunctions, a wafer stage is not level, and/or a flow optimizer induces too much shift, among other examples), the copper atoms are less susceptible to small re-directions from external noise. As a result, back end of line (BEOL) and/or middle end of line (MEOL) conductive structures are formed in a more uniform manner, which increases conductivity and improves lifetime of an electronic device including the BEOL and/or MEOL conductive structures.

Semiconductor tool for copper deposition

The present disclosure describes an exemplary method that can prevent or reduce out-diffusion of Cu from interconnect layers to magnetic tunnel junction (MTJ) structures. The method includes forming an interconnect layer over a substrate that includes an interlayer dielectric stack with openings therein; disposing a metal in the openings to form corresponding conductive structures; and selectively depositing a diffusion barrier layer on the metal. In the method, selectively depositing the diffusion barrier layer includes pre-treating the surface of the metal; disposing a precursor to selectively form a partially-decomposed precursor layer on the metal; and exposing the partially-decomposed precursor layer to a plasma to form the diffusion barrier layer. The method further includes forming an MTJ structure on the interconnect layer over the diffusion barrier layer, where the bottom electrode of the MTJ structure is aligned to the diffusion barrier layer.

Diffusion barrier layer on interconnection vias for magnetic tunnel junctions

Diffusion layer for magnetic tunnel junctions

Growing community of inventors

Hsinchu, Taiwan

Jui-Hung Ho